The invention relates to a refiner for beating and dissociating pulp, in particular, a refiner having a plurality of conical-type rotors.
Among refiners, such as a disc-type refiner, a conical-type refiner and a drum-type refiner, the conical-type refiner includes a conical-type rotor in a substantially cone-shape, on the surface of which a plurality of bars is provided, and a stator disposed to face the conical-type rotor.
However, in the refiner having the single conical-type rotor as described above, when the pulp is beaten and dissociated through the rotation of the single conical-type rotor, a pressure difference is generated between a material outlet and a portion between the single conical-type rotor and the stator facing the rotor, to thereby allow the space between the single conical-type rotor and the stator to be wider or narrower. Thus, a thrust load is generated in an axial direction of a rotating shaft where the single conical-type rotor is attached.
Therefore, a bearing for holding the rotating shaft of the conical-type rotor must be mechanically formed with a structure coping with the thrust load. Moreover, there has been a problem such that an energy loss due to the thrust load takes place.
In view of the above problems, the present invention has been made and an object of the invention is to provide a refiner to obviate the above problems.
Further objects and advantages of the invention will be apparent from the following description of the invention.
In order to attain the above-stated objects, according to a first aspect of the invention, a refiner includes a driving source, a rotating shaft rotated by the driving source, a conical-type rotor attached to the rotating shaft, and stators disposed in a casing to face the conical-type rotor. The conical-type rotor has a first conical portion in a substantially cone-shape and a second conical portion in a substantially cone-shape, and a bottom portion of the first conical portion and a bottom portion of the second conical portion are joined together. The rotating shaft passes through top portions of the first conical portion and the second conical portion, and the conical-type rotor is attached to the rotating shaft.
Also, according to a second aspect of the invention, in the refiner according to the first aspect, one end side of the rotating shaft is made free without being supported thereat, and the other end side thereof is held so that the rotating shaft is movable in a longitudinal direction thereof. The conical-type rotor is attached to the free one end side of the rotating shaft. A raw material supply path includes a first material supply path and a second material supply path. The first material supply path communicates with a chamber where the first conical portion is positioned, and the second material supply path communicates with a chamber where the second conical portion is positioned, respectively.
Also, according to a third aspect of the invention, in the refiner according to the first aspect, the conical-type rotor is divided into the first conical portion and the second conical portion. The first conical portion has therein a first hollow portion communicating with the first bottom portion of the first conical portion, and the second conical portion has therein a second hollow portion communicating with the second bottom portion of the second conical portion. The conical-type rotor is formed by abutting the first bottom portion against the second bottom portion to thereby form a hollow portion communicating with the first hollow portion and the second hollow portion in the conical-type rotor.
Also, according to a fourth aspect of the invention, in the refiner according to the first aspect, the conical-type rotor is divided into the first conical portion and the second conical portion. The first bottom portion of the first conical portion is open and includes a first outer peripheral edge and a first inner peripheral edge located inside the first outer peripheral edge, and the second bottom portion of the second conical portion is open and includes a second outer peripheral edge and a second inner peripheral edge located inside the second outer peripheral edge. The conical-type rotor is formed by abutting the first inner peripheral edge against the second inner peripheral edge and abutting the first outer peripheral edge against the second outer peripheral edge, respectively, to thereby form the hollow portion communicating with the first and second bottoms in the conical-type rotor.
Also, according to a fifth aspect of the invention, in the refiner according to the first aspect, the conical-type rotor includes a boss portion abutting against an outer periphery of the rotating shaft, and the first and second conical portions abut against an outer periphery of the boss portion. The first and second conical portions have the same shape. The first bottom portion of the first conical portion is open, and includes the first outer peripheral edge and the first inner peripheral edge located inside the first outer peripheral edge. The second bottom portion of the second conical portion is open, and includes the second outer peripheral edge and the second inner peripheral edge located inside the second outer peripheral edge. The conical-type rotor is formed by abutting the first inner peripheral edge against the second inner peripheral edge and abutting the first outer peripheral edge against the second outer peripheral edge, respectively, to thereby form the hollow portion communicating with the first and second bottoms in the conical-type rotor.
Also, according to a sixth aspect of the invention, there is manufactured a refiner having an apparatus main portion including a driving source, a rotating shaft rotated by the driving source, a beating and dissociating portion, i.e. processing portion, attached to the rotating shaft and having a first portion and a second portion, a first casing having a first material supply path communicating with a chamber where the first portion is positioned and a second casing having a second material supply path communicating with a chamber where the second portion is positioned. It is possible to form a double conical-type rotor having a plurality of conical-type beating and dissociating portions or a double disc-type rotor having a plurality of disc-type beating and dissociating portions. In a method for manufacturing the refiner, the apparatus main portion is used commonly. In case of the refiner having the double conical-type rotor, the conical-type rotor with a substantially cone-shape first conical portion and a substantially cone-shape second conical portion are formed so that bottom portions of the first conical portion and the second conical portion are joined together, a third casing is located between the first casing and the second casing, and the conical-type rotor is housed in the third casing, the first casing and the second casing. In case of the refiner having the double disc-type rotor, the double disc-type rotor is housed in the first casing and the second casing.